UNITED NATIONS (Reuters) -- UN Secretary-General Ban Ki-moon has welcomed a U.S.-Russian pledge
to join forces to eradicate atomic weapons and use diplomacy to deal with Iran and North Korea's nuclear programs.
"The secretary-general believes that their leadership is vital to the process leading to the achievement of a nuclear-weapon-free world," UN spokesman Farhan Haq told reporters on April 3.
Russian President Dmitry Medvedev and U.S. President Barack Obama pledged at a London summit on April 1 to seek a deal by July on cutting their nuclear arsenals, work for a nuclear-free world and coordinate policy on Iran and North Korea.
Ban welcomes these "significant undertakings," Haq said.
Nuclear diplomacy and arms control were given short shrift by Obama's predecessor, George W. Bush, who abandoned previous U.S. commitments to proceed with nuclear disarmament.
North Korea announced in October 2006 it had conducted a nuclear test and is expected to launch a long-range rocket in the coming days. Iran has continued to expand a secretive uranium enrichment campaign it says will produce fuel for power plants but which Western countries suspect is for weapons.
Haq said Ban was particularly pleased that Obama announced he would work for U.S. ratification of the Comprehensive Nuclear Test Ban Treaty, a pact that bans all nuclear explosions for civilian or military purposes.
The United States signed the treaty but never ratified it. The Senate rejected the treaty in 1999 and the Bush administration refused to resubmit it. Officials under Bush said they feared it would unnecessarily limit U.S. military research options.
The pact will not enter into force until it is ratified by the United States, China and other countries that had nuclear reactors at the time it was negotiated in 1994-96.